JCU > Research Portfolio > Dr Alexandra Roberts

About

Alex uses genetic, proteomic and metabolomic approaches to study both infectious and chronic diseases.

She is currently funded by a Queensland Accelerate Fellowship to characterise the virulence mechanisms of the chytrid fungus Batrachochytrium dendrobatidis, a pathogen that has caused massive population declines in frog species worldwide. Alex is also funded by a JCU Rising Star Grant to study how oxidative stress can drive obesity-linked liver cancer.

Her previous research has focused on thiol-dependent antibiotic resistance and oxidative stress protection in Firmicutes, iron sequestration in marine actinomycetes, and the biosynthesis of cyanobacterial toxins.

Interests

Research

Enzymology
Virulence mechanisms
Amphibian chytrid fungus
Chytridiomycosis
Liver cancer
Metabolomics
Oxidative stress

Experience

2018 to present - Lecturer - Molecular and Cell Biology, James Cook University (Townsville, Australia)
2013 to present - Research Fellow, James Cook University (Townsville, Australia)
2010 to 2012 - Senior Research Associate, University of East Anglia (Norwich, UK)
2008 to 2010 - Postdoctoral Researcher, Scripps Institution of Oceanography at University of California San Diego (San Diego, USA)
2004 to 2009 - PhD Microbiology and Immunology, University of New South Wales (Sydney, Australia)

Research Disciplines

Honours

Fellowships

2015 to 2018 - Accelerate Fellowship - Department of Science, Information Technology, Innovation and the Arts
2016 to 2017 - Rising Star Grant - James Cook University
2004 to 2008 - Australian Postgraduate Award
2004 to 2008 - CRC for Water Quality and Treatment Postgraduate Award

Memberships

2016 - Member of the Australian Society for Microbiology
2016 - Member of the Australian Society for Biochemistry and Molecular Biology

Publications

These are the most recent publications associated with this author. To see a detailed profile of all publications stored at JCU, visit ResearchOnline@JCU. Hover over Altmetrics badges to see social impact.

Journal Articles

Dewdney B, Alanzay M, Gillman R, Walker S, Wankell M, Qiao L, George J, Roberts A and Hebbard L (2020) The effects of fructose and metabolic inhibition on hepatocellular carcinoma. Scientific Reports, 10, Article: 16769, DOI:10.1038/s41598-020-73653-5.
Dewdney B, Roberts A, Qiao L, George J and Hebbard L (2020) A sweet connection? Fructose’s role in hepatocellular carcinoma. Biomolecules, 10 (4), Article: 496, DOI:10.3390/biom10040496.
Claytor S, Gummer J, Grogan L, Skerratt L, Webb R, Brannelly L, Berger L and Roberts A (2019) Susceptibility of frogs to chytridiomycosis correlates with increased levels of immunomodulatory serotonin in the skin. Cellular Microbiology, 21 (10), Article: e13089, DOI:10.1111/cmi.13089..
Kosch T, Silva C, Brannelly L, Roberts A, Lau Q, Marantelli G, Berger L and Skerratt L (2019) Genetic potential for disease resistance in critically endangered amphibians decimated by chytridiomycosis. Animal Conservation, 22 (3), pp. 238-250, DOI:10.1111/acv.12459.
Roberts A, Berger L, Robertson S, Webb R, Kosch T, McFadden M, Skerratt L, Glass B, Motti C and Brannelly L (2019) The efficacy and pharmacokinetics of terbinafine against the frog-killing fungus (Batrachochytrium dendrobatidis). Medical Mycology, 57 (2), pp. 204-214, DOI:10.1093/mmy/myy010.
Webb R, Berger L, Skerratt L and Roberts A (2019) A rapid and inexpensive viability assay for zoospores and zoosporangia of Batrachochytrium dendrobatidis. Journal of Microbiological Methods, 65, Article: 105688, DOI:10.1016/j.mimet.2019.105688.
Brannelly L, Roberts A, Skerratt L and Berger L (2017) Epidermal cell death in frogs with chytridiomycosis. PeerJ, 5, Article: e2925, pp. 1-20, DOI:10.7717/peerj.2925.
Scheele B, Skerratt L, Grogan L, Hunter D, Clemann N, McFadden M, Newell D, Hoskin C, Gillespie G, Heard G, Brannelly L, Roberts A and Berger L (2017) After the epidemic: ongoing declines, stabilizations and recoveries inamphibians afflicted by chytridiomycosis. Biological Conservation, 206, pp. 37-46, DOI:10.1016/j.biocon.2016.12.010.
Berger L, Roberts A, Voyles J, Longcore J, Murray K and Skerratt L (2016) History and recent progress on chytridiomycosis in amphibians. Fungal Ecology, 19, pp. 89-99, DOI:10.1016/j.funeco.2015.09.007.
Wang W, He Y, Yu G, Li B, Sexton D, Wileman T, Roberts A, Hamilton C, Liu R, Chao Y, Shan Y and Bao Y (2015) Sulforaphane protects the liver against CdSe quantum dot-induced cytotoxicity. PLoS ONE, 10 (9), Article: e013877, pp. 1-17, DOI:10.1371/journal.pone.0138771.
Gaballa A, Chi B, Roberts A, Becher D, Hamilton C, Antelmann H and Helmann J (2014) Redox regulation in Bacillus subtilis: the bacilliredoxins BrxA(YphP) and BrxB(YqiW) function in de-bacillithiolation of S-bacillithiolated OhrR and MetE. Antioxidants & Redox Signaling, 21 (3), pp. 357-367, DOI:10.1089/ars.2013.5327.
Luan H, Meng N, Fu J, Chen X, Xu X, Feng Q, Jiang H, Dai J, Yuan X, Lu Y, Roberts A, Luo X, Chen M, Xu S, Li J, Hamilton C, Fang C and Wang J (2014) Genome-wide transcriptome and antioxidant analyses on gamma-irradiated phases of Deinococcus Radiodurans R1. PLoS ONE, 9 (1), Article: e85649, pp. 1-11, DOI:10.1371/journal.pone.0085649.

More: ResearchOnline@JCU stores 27+ research outputs authored by Dr Alexandra Roberts from 2007 onwards.

Current Funding

Current and recent Research Funding to JCU is shown by funding source and project.

Australasian Mycological Society - Research Awards

Glutathione biosynthesis in the amphibian fungus, Batrachochytrium dendrobatidis.

Indicative Funding: $3,000 over 1 year
Summary: What makes a successful fungal pathogen? In this project we aim to determine the role of glutathione in fungal pathogenesis. In doing so we will develop and optimise gene knockdown protocols, which can be used more broadly to assess other virulence factors. Specifically, we will: 1: Explore glutathione biosynthesis in virulent and less- virulent strains of Bd, both in vitro and in vivo. 2: Characterise the role of glutathione in pathogenesis using knockdown techniques.
Investigators: Rebecca Webb, Catherine Rush and Alexandra Roberts in collaboration with Lee Berger and Lee Skerratt (College of Public Health and Medical & Vet Sciences)
Keywords: Glutathione biosynthesis; Pathogensis; Chytrid Fungus

Ecological Society of Australia - Holsworth Wildlife Research Endowment

RNAi as a novel antifungal treatment for endangered frogs

Indicative Funding: $9,390 over 3 years
Summary: This project aims to develop a novel method to treat fungal diseases. RNA interference (RNAi) is a cutting edge technique in which small interfering RNA (siRNA) silences genes of interest. I aim to use siRNA to target virulence genes of the fungal disease `amphibian chytrid fungus? in the hope that this can be developed into therapeutic. This will be the first time RNAi has been manipulated in this fungi species, and also the first instance of using siRNA as an antifungal treatment for an animal.
Investigators: Rebecca Webb, Alexandra Roberts, Lee Berger and Lee Skerratt (College of Public Health and Medical & Vet Sciences)
Keywords: RNA interference; Health; Wildlife; Antifungal; Virulence; Biosecurity

Morris Animal Foundation - Pilot Studies

Saving endangered frogs: Using RNA Interference to reduce the virulence of the Frog-killing fungus

Indicative Funding: $13,800 over 2 years
Summary: This project aims to mitigate the effect of fungal diseases via small interfering RNA (siRNA) using Batrachochytrium dendrobatidis (Bd) infection in amphibians as a model system. Bd produces metabolites that suppress frog immunity, therefore, siRNAs will be developed to inhibit immunosuppressant production and improve host survival. First, siRNAs will be transfected into the pathogen, to confirm gene silencing and determine the effect on growth and virulence. Effective siRNAs will then be tested in vivo by spraying topically onto infected frogs, to improve disease resistance.
Investigators: Alexandra Roberts in collaboration with Lee Berger, Rebecca Webb and Lee Skerratt (College of Public Health and Medical & Vet Sciences)
Keywords: Amphibian Declines; Virulence; Antifungal treatment; Chytrid

Queensland Department of Environment and Science - Accelerate Fellowships

How the fungus kills the frog: Determining the mechanisms of chytrid virulence

Indicative Funding: $180,000 over 4 years, in partnership with Taronga Conservation Society Australia ($30,000)
Summary: The fungal disease chytridiomycosis has caused global extinctions of amphibians, including six Australian frog species ? all of them from Queensland. Five more Queensland frog species are endangered and two are critically endangered. These species will likely become extinct unless intensive management strategies for chytridiomycosis are implemented. The causative fungus (Batrachochytrium dendrobatidis) inhibits the frog immune system and damages the skin, leading to death via cardiac arrest. However, the lack of understanding of how the fungus causes these effects has undermined effective disease management. To address this problem, I will firstly identify virulence factors that will enable the development of novel diagnostic screens, to map the distribution of virulent strains in the wild. This approach will identify hotspots of high risk for future disease outbreaks. Secondly, I will develop targeted drugs to overcome immunosuppression and enhance vaccination against the disease. Lastly, viruses of fungi will be investigated to find suitable biocontrol agents that will kill the fungus, and hence, treat infected frogs in captivity and in the wild. Overall, this project will inform management and frog reintroduction practices in Queensland to help control the spread and impact of this devastating disease, and ultimately safeguard our unique amphibian biodiversity.
Investigators: Alexandra Roberts (College of Public Health and Medical & Vet Sciences)
Keywords: Amphibian Chytrid Fungus

QLD Department of Environment and Science - Advance Queensland Women's Academic Fund

New Methods To Protect Frogs From Chytridiomycosis

Indicative Funding: $13,000
Summary: Amphibians are under threat from the frog-killing fungus, which causes the fatal skin disease chytridiomycosis. My research investigates new methods to protect captive and wild frogs from chytridiomycosis, including testing new therapeutics and characterising virulence mechanisms of the pathogen. The Advance Queensland Women?s Academic Fund supports women in maintaining their research careers, and supports Queensland Organisations in promoting the achievements of Queensland?s female researchers. The funding can be used to employ a research assistant to continue research progress while on parental leave.
Investigators: Alexandra Roberts, Lee Berger and Richard Webb (College of Public Health and Medical & Vet Sciences)
Keywords: Chytrid Fungus; Amphibian Declines; Antifunal treatments; Molecular Biology

Supervision

Advisory Accreditation: I can be on your Advisory Panel as a Primary or Secondary Advisor.

These Higher Degree Research projects are either current or by students who have completed their studies within the past 5 years at JCU. Linked titles show theses available within ResearchOnline@JCU.

Current

Reducing Virulence of Fungal Pathogens using Genetics Tools (PhD , Primary Advisor)

Completed

The role of serotonin and glutathione in the pathogenesis of chytridiomycosis (2021, PhD , Secondary Advisor)
Characterising the role of fructose metabolism in hepatocellular carcinoma (2021, PhD , Secondary Advisor)

Collaboration

The map shows research collaborations by institution from the past 7 years.
Note: Map points are indicative of the countries or states that institutions are associated with.